Method for forming a tunnel in a bone

ABSTRACT

A method for forming a tunnel in a bone. The method includes forming a first tunnel in the bone, the tunnel having a longitudinal axis, inserting a first drill guide into the first tunnel, supporting a first tunnel-forming device along an axis defining a first offset relative the longitudinal axis of the first tunnel with the first drill guide, and forming a second tunnel alongside the first tunnel with the first tunnel-forming device, the second tunnel communicating with the first tunnel and defining a single elongated opening.

INTRODUCTION

During anterior or posterior cruciate ligament reconstruction surgeryfor the knee, femoral and tibial tunnels are drilled for securing agraft ligament to the tibia and femur. Various drill guides or aimersare known for guiding a drilling device to form these tunnels.

Although the existing drill guides can be satisfactory for theirintended purposes, there is still a need for additional procedures anddevices that facilitate drilling femoral and tibial bone tunnels.

SUMMARY

The present teachings provide a method for forming a tunnel in a bone.The method includes forming a first tunnel in the bone, the tunnelhaving a longitudinal axis, inserting a first drill guide into the firsttunnel, supporting a first tunnel-forming device along an axis defininga first offset relative the longitudinal axis of the first tunnel withthe first drill guide, and forming a second tunnel alongside the firsttunnel with the first tunnel-forming device, the second tunnelcommunicating with the first tunnel and defining a single elongatedopening.

The present teachings also provide a method for forming a tunnel in abone and includes forming a first tunnel in the bone, the first tunnelhaving a longitudinal axis, inserting into the first tunnel a firstdrill guide having a guiding bore with an axis defining a first offsetrelative to the longitudinal axis of the first tunnel, supporting afirst tunnel-forming device on the first drill guide such that alongitudinal axis of the first tunnel-forming device coincides with theaxis of the guiding bore and the first tunnel-forming device extends atleast partially outside the first tunnel in a transverse directionrelative to the longitudinal axis of the first tunnel, and drilling withthe first tunnel-forming device a second tunnel parallel to andcommunicating with the first tunnel along the longitudinal direction.

The present teachings further provide a method for forming a tunnel in abone. The method includes inserting a guide pin in the bone, positioninga cannulated tunnel-forming device over the guide pin, drilling with thecannulated tunnel-forming device a first tunnel in the bone, the firsttunnel having a longitudinal axis, and removing the guide pin and thecannulated tunnel-forming device. The method further includes insertinginto the first tunnel a first drill guide having a guiding bore with anaxis defining a first offset relative to the longitudinal axis of thefirst tunnel, supporting a first tunnel-forming device on the firstdrill guide such that a longitudinal axis of the first tunnel-formingdevice coincides with the axis of the guiding bore and the firsttunnel-forming device extends at least partially outside the firsttunnel in a transverse direction relative to the longitudinal axis ofthe first tunnel, and drilling with the first tunnel-forming device asecond tunnel parallel to and communicating with the first tunnel alongthe longitudinal direction and in the direction of the offset, whereinthe first and second tunnels define an elongated opening, the elongatedopening being elongated in the direction of the first offset.

Further areas of applicability of the present invention will becomeapparent from the description provided hereinafter. It should beunderstood that the description and specific examples are intended forpurposes of illustration only and are not intended to limit the scope ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is a perspective view of a drill guide device according to thepresent teachings;

FIG. 2 is a side view of the drill guide device of FIG. 1;

FIG. 3 is front view of the drill guide device of FIG. 1;

FIG. 4 is another a perspective view of the drill guide device of FIG.1;

FIG. 5 is a side perspective view of a drill guide device according tothe present teachings, the drill guide device shown with atunnel-forming device;

FIG. 6 is a front perspective view of the drill guide device of FIG. 5;

FIG. 7 is a sectional view of the drill guide device of FIG. 5;

FIG. 8 is a side perspective view of a drill guide device according tothe present teachings, the drill guide device shown with atunnel-forming device;

FIG. 9 is a front perspective view of the drill guide device of FIG. 8;

FIG. 10 is a sectional view of the drill guide device of FIG. 8;

FIG. 11 is an environmental view showing a cannulated tunnel-formingdevice over a guide pin in a tibial tunnel;

FIG. 12 is an environmental view showing the drill guide device of FIG.5 in a tibial tunnel;

FIG. 13 is an environmental view showing the drill guide device of FIG.8 in a tibial tunnel; and

FIG. 14 is a view showing exemplary cross-sections of a bone tunnelformed according to the present teachings.

DESCRIPTION OF VARIOUS ASPECTS

The following description is merely exemplary in nature and is in no wayintended to limit the invention, its application, or uses. For example,although the present teachings are illustrated for cruciate ligamentreconstruction in knee surgery, the present teachings can be used forre-shaping any tunnel in a long bone, including the tibia and femur.

Referring to FIGS. 1-7, 11, 12 and 14, an exemplary drill guide device100 according to the present teachings can be used to change the shapeof an existing or first bone tunnel 84 during cruciate ligamentreconstruction. The first bone tunnel 84 can have substantially circularcross-section and can be initially drilled over a guide wire or a guidepin 140 in the tibia 82 or femur 80 by conventional methods using, forexample, a cannulated tunnel-forming device 142, as shown in FIG. 11.The guide wire 140 and the cannulated tunnel-forming device 142 can thenbe removed. The drill guide device 100 can be used to change the shapeof the cross-section of the first bone tunnel 84 from circular to oval,egg-shaped, pear-shaped, elongated, eight-shaped, or asymmetric in adesired orientation including the anterior, posterior, medial or lateraldirections, or any other shape, as discussed below. The drill guidedevice 100 can be used after such change in the shape of the first bonechannel 84 is made to further change the new cross-section, as discussedbelow. The new shape of the first bone tunnel 84 can be selected forproviding a desired anatomic orientation, path/shape and placement ofthe ligament grafts, as determined by the surgeon. For example, bonetunnels with elongated cross-sections can be used for accommodatingseveral strands of ligament grafts, and can also be used to approximatethe shape and path of the anterior or posterior cruciate ligaments. Theelongated shape can be made by drilling a new tunnel alongside andcommunicating with first bone tunnel 84 as illustrated in FIG. 14, anddiscussed below.

The drill guide device 100 can include an arm 102, a drill guide 104extending from the arm 102, and a support member 106, which can be usedto secure the drill guide device 110 to the bone and can also functionas a handle. The support member 106 can have first and second portions106 a and 106 b. The arm 102 can be supported either fixedly orremovably on its proximal end on the first portion 106 a of the supportmember 106 at an angle of about 90-degrees for exerting axial force. Thesecond portion 106 b can be oriented at a different angle relative tothe arm 102, for ergonomic considerations and for avoiding the patient'sanatomy. The arm 102 can be in the form of a semi-cylindrical shafthaving an open-channel cross-section 116 or as an incomplete/open tube,adapted for receiving and guiding a drill, any other drilling/reamingdevice, a trephine, or generally any tunnel-forming device 110, suchthat a portion of the tunnel-forming device extends outside thecross-section 116 of the arm 102 to be exposed to form the tunnel.

Referring to FIGS. 4 and 6, the drill guide 104 can be bullet-shaped,and include a proximal portion 120 and a distal portion 114, which isfirst inserted into the bone tunnel. The proximal portion 120 can becylindrical, and the distal portion 114 can be conical with a bluntclosed tip 112. The proximal portion 120 can have a cross-section in theform of a complete circle, as shown in FIG. 4, or can be a portion of acircle with an arc cut off as shown in FIG. 6.

The outer surface of the first portion 120 can substantially conform tothe shape of the first bone tunnel 84. If the first bone tunnel 84 iscircular, then the drill guide 100 can have a circular cross-sectionwith a diameter that corresponds to the diameter of the bone tunnel 84,such that the drill guide 104 can be inserted in the first bone tunnel84. The proximal and distal portions 120, 114 of the drill guide 104 areconcentric and define a longitudinal axis A that substantially coincideswith the bone tunnel axis when the drill guide 104 is inserted into thebone tunnel 84, as illustrated in FIG. 12. A tunnel-forming devicehaving a longitudinal drill axis B can seat on an inner surface 122 ofthe arm 102 and be guided by the drill guide 104, as shown in FIGS. 5and 6, such that the drill axis B is parallel and offset relative to theaxis A by an offset distance D. The tunnel-forming device can include adistal shaft 111, which can be received in an internal guiding bore 124of the drill guide 104. The guiding bore 124 defines an axis B whichcoincides with the drill axis B. The offset D allows the tunnel-formingdevice to extend the diameter TD of the bone tunnel 84 in a selecteddirection C to define a new cross-section that is elongated in thedirection of the axis C, such as the exemplary cross-sectional shapesshown at 84 a, 84 b in FIG. 14. The new cross-sectional shape can be anyshape with an elongated axis, including eight-shaped, oval, pear oregg-shaped and other elongated shapes with one or two axes of symmetry.

Referring to FIGS. 8-10, 13 and 14, the drill guide device 100 caninclude a drill guide 104 that can be used with a second bone tunnel 84b that has already been elongated in the direction C, as discussedabove. The drill guide 104 can have a cross-sectional shape 130 thatcorresponds to the elongated shape of the second tunnel 84 b, such thatthe drill guide 104 can be inserted in the second bone tunnel 84 b forelongating further the second bone tunnel 84 b to a third bone tunnel 84c with a new shape. For example, the drill guide 104 can include firstand second distal portions 114 arranged one above the other and havingcorresponding longitudinal axes A and A′, as shown in FIG. 9. The firstand second distal portions 114 can be made as single unitary part of thedrill guide or can be separate, but modularly connected portions. Aguiding bore 124 in the drill guide 104 defines an axis B′ whichcoincides with the drill axis and is offset from the second axis A′ byan offset distance D. It should be appreciated that the offset distanceD can have many different values and is not necessarily equal to theoffset distance D between axes A and B shown in FIG. 7. Further, theadditional elongation of the tunnel 84 b to a new tunnel 84 c can beprovided in the same, opposite or other different direction than thedirection of the initial elongation, as shown, for example, in FIG. 14,which illustrated two elongations 84 c in opposite directions relativeto the first bone tunnel 84.

Referring to FIGS. 12 and 14, a first drill guide 104 with a singledrill guide axis A, such as the one shown in FIG. 5, is inserted in afirst bone tunnel 84 of circular cross-section, which was formed, forexample, as discussed above in connection with FIG. 11. The first drillguide 104 can align a first tunnel-forming device along an axis Bparallel and offset by a distance D from the drill guide axis A, suchthat the first tunnel-forming device extends at least partially outsidethe first bone tunnel 84 in a direction transverse to the axis A, whichalso coincides with the longitudinal axis of the first bone tunnel 84.The first tunnel-forming device can be operated to drill another tunnelalongside and communicating with the first tunnel 84 such that theresulting new tunnel defines a second bone tunnel 84 b with an elongatedopening. The first drill guide 104 and the first tunnel-forming deviceare then removed.

Referring to FIGS. 12 and 13, a second drill guide 104 with first andsecond parallel axes A, A′ can be inserted in a second bone tunnel 84 bthat has an elongated cross-section. The elongated cross-section of thesecond bone tunnel 84 b can be created as discussed above in connectionwith FIG. 11. A second tunnel-forming device is guided along an axis B′which is offset from the second axis A′ by an offset distance D, suchthat the second tunnel-forming device extends at least partially outsidethe second bone tunnel 84 b in a direction transverse to the axes A andA′. The offset distance D can further elongate the second bone tunnel 84b to a third bone tunnel 84 c that has a more elongated cross-section.The second tunnel-forming device can be the same as the firsttunnel-forming device, or can be a different tunnel-forming devicehaving a different diameter.

It will be appreciated that although methods according to the presentteachings are illustrated in FIGS. 11-13 in relation to a tibia, thepresent teachings are similarly applicable in relation to other bones,including the femur. Further, although a few exemplary shapes of bonetunnels elongated in one direction and its opposite are illustrated inFIG. 14, other shapes elongated in different directions other than thedirection C and its opposite, can be similarly obtained, includingelongations in the anterior, posterior, lateral or medial directions ofthe bone. Such shapes can be used to accommodate the path andorientations of multiple cruciate ligament grafts without undulyinterfering with the patient's anatomy or occupying excessive bulk incomparison with circular cross-sections sized to accommodate severalstrand of ligament grafts. Variations of the shape of the bone tunnelcan be obtained by varying, for example, the amount of each offset, thediameter of the tunnel-forming device used for each offset, at least onediameter of each drill guide, or the direction of each offset.

The foregoing discussion discloses and describes merely exemplaryarrangements of the present invention. One skilled in the art willreadily recognize from such discussion, and from the accompanyingdrawings and claims, that various changes, modifications and variationscan be made therein without departing from the spirit and scope of theinvention as defined in the following claims.

1. A method for forming a tunnel in a bone comprising: forming a firsttunnel in the bone, the tunnel having a longitudinal axis; inserting afirst drill guide into the first tunnel; supporting a firsttunnel-forming device along an axis defining a first offset relative thelongitudinal axis of the first tunnel with the first drill guide; andforming a second tunnel alongside the first tunnel with the firsttunnel-forming device, the second tunnel communicating with the firsttunnel and defining a single elongated opening.
 2. The method of claim1, wherein forming the second tunnel comprises elongating across-section of the first tunnel in the direction of the first offset.3. The method of claim 1, wherein the single opening has a cross-sectionselected from egg-shaped, pear-shaped, eight-shaped, or oval.
 4. Themethod of claim 1, further comprising: removing the first drill guideand the first tunnel-forming device; inserting a second drill guide intothe elongated opening, the second drill guide having a cross-sectionconforming to the cross-section of the elongated opening; supporting asecond tunnel-forming device on the second drill guide axially offset ata second offset from the second drill guide; and drilling with thesecond tunnel-forming device a third tunnel communicating with andalongside the elongated opening in the direction of the second offset.5. The method of claim 4, wherein the first and second offsets areunequal.
 6. The method of claim 4, wherein the first and second offsetsare oriented in different directions.
 7. The method of claim 4, whereinthe first and second offsets are oriented in opposite directions.
 8. Themethod of claim 4, wherein the first and second offsets are oriented insubstantially the same direction.
 9. The method of claim 4, wherein thefirst and second tunnel-forming devices have different diameters. 10.The method of claim 4, wherein at least one of the first and seconddrill guides and at least one of the first tunnel-forming device andsecond tunnel-forming devices have unequal diameters.
 11. The method ofclaim 4, wherein at least one of the first and second drill guides andat least one of the first tunnel-forming device and secondtunnel-forming devices have substantially equal diameters.
 12. Themethod of claim 1, wherein the first drill guide includes a guiding boreand a portion of the first tunnel-forming device is partially receivedin the guiding bore.
 13. A method for forming a tunnel in a bonecomprising: forming a first tunnel in the bone, the first tunnel havinga longitudinal axis; inserting into the first tunnel a first drill guidehaving a guiding bore with an axis defining a first offset relative tothe longitudinal axis of the first tunnel; supporting a firsttunnel-forming device on the first drill guide such that a longitudinalaxis of the first tunnel-forming device coincides with the axis of theguiding bore and the first tunnel-forming device extends at leastpartially outside the first tunnel in a transverse direction relative tothe longitudinal axis of the first tunnel; and drilling with the firsttunnel-forming device a second tunnel parallel to and communicating withthe first tunnel along the longitudinal direction.
 14. The method ofclaim 13, wherein drilling the second tunnel comprises elongating across-section of the first tunnel in the direction of the first offset.15. The method of claim 14, wherein elongating the cross-section of thefirst tunnel comprises forming a cross-section selected from egg-shaped,pear-shaped, eight-shaped, or oval.
 16. The method of claim 14, whereinsupporting the first tunnel-forming device on the drill guide comprisesinserting at least a portion of a shaft of the first tunnel-formingdevice in the guiding bore.
 17. A method for forming a tunnel in a bonecomprising: inserting a guide pin in the bone; positioning a cannulatedtunnel-forming device over the guide pin; drilling with the cannulatedtunnel-forming device a first tunnel in the bone, the first tunnelhaving a longitudinal axis; removing the guide pin and the cannulatedtunnel-forming device; inserting into the first tunnel a first drillguide having a guiding bore with an axis defining a first offsetrelative to the longitudinal axis of the first tunnel; supporting afirst tunnel-forming device on the first drill guide such that alongitudinal axis of the first tunnel-forming device coincides with theaxis of the guiding bore and the first tunnel-forming device extends atleast partially outside the first tunnel in a transverse directionrelative to the longitudinal axis of the first tunnel; and drilling withthe first tunnel-forming device a second tunnel parallel to andcommunicating with the first tunnel along the longitudinal direction andin the direction of the offset, wherein the first and second tunnelsdefine an elongated opening, the elongated opening being elongated inthe direction of the first offset.
 18. The method of claim 17, furthercomprising: removing the first drill guide and the first tunnel-formingdevice; inserting a second drill guide into the elongated opening, thesecond drill guide having a cross-section conforming to thecross-section of the elongated opening; supporting a secondtunnel-forming device on the second drill guide axially offset at asecond offset from the second drill guide; and drilling with the secondtunnel-forming device a third tunnel communicating with and alongsidethe elongated opening in the direction of the second offset.
 19. Themethod of claim 18, wherein the first and second offsets are unequal.20. The method of claim 18, wherein the first and second offsets areoriented in different directions.